Radio

I  INTRODUCTION Radio Frequency and Wavelength RangesRadio waves have a wide range of applications, including communication during emergency rescues (transistor and shortwave radios), international broadcasts (satellites), and cooking food (microwaves). A radio wave is described by its wavelength, the distance from one crest to the next, or its frequency, the number of crests that move past a point in one second. Wavelengths of radio waves range from 100,000...

Read More

Railroads

I  INTRODUCTION Railway Control Room Computerized control rooms allow railroad personnel to monitor activity on many railroad or subway lines simultaneously. Computers have greatly increased the safety and efficiency of rail transportation. This control room coordinates rail activity at Victoria Station in London.Railroads, roads on which trains of freight...

Read More